Nis johnson



( No Model.)

N. JOHNSON. EXTENSIBLE STANDARD FOR PIANO LAMPS.

No. 453,865. Patented June 9, 1891.

r mmmmm lNi/rn TATES NIS JOHNSON, OF MERIDEN, CONNECTICUT, ASSIGNOR TO lllE ATENT OFFICE.

MERIDEN BRONZE COMPANY, OF SAVE PLACE.

SPECIFICATION forming part of Letters Patent No. 453,865, dated June 9,

Application filed July 17, 1890. Serial No. 359,032. (No model.)

To all whom it may concern,-

Be it known that 1, NE JOHNSON, of Meriden, in the county of New Haven and State of Connecticut, have invented a new Improvement in Extensible Standards for Piano- Lamps; and I do hereby declare the following, when taken in connection with accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, in-

Figure 1, a view in vertical central section of an extensible standard constructed in aceordance with my invention; Fig. 2, a detached View in side elevation of one of the friction-plates. Fig. 3 is a section online a: a: of Fig. 1.

My invention relates to an improvementin extensible standards for piano-lamps, the ob ject being to produce a simple, reliable, and elfective friction-clutch for sustaining the inner tube of the devicein its adjusted position under the weight of the lamp and the lampshade.

lVith these ends in view my invention consists in the construction hereinafter described, and particularly recited in the claims.

Under my invention the lower end of the inner tube A terminates in a cone B, in this instance formed by a plug inserted thereinto. Upon this cone two longitudinally and laterally movable tapering concavo-convex friction -plates C C have bearing, and are moved up and down over the same for engaging them with and disengaging them from the walls of the stationary outer tubes of the standard. Each of the said. plates has a perforation E formed in its narrower lower end to adapt them to respectively receive pins F F, radially projecting from opposite points in the periphery of a collar G, and made long enough to permit the plates to move laterally uponthem, but of course within narrow limits. The outer faces of the said plates are countersunk around their perforations to permit the ends of the pins to be headed down to prevent the plates from dropping off when the inner tube is pulled out of the outer tube. By thus attaching the plates to the said collar G their free upper ends are allowed consid erable lateral play toward and away from each other. The said collar is adjustably mounted upon the threaded lower end A of the operating-rod ll, which is located in the inner tube and projects through and below the cone E, in which it has bearing. By adjusting the collar upon this rod, as provided for, the friction-plates may be raised or lowered with respect to the cone, as may be required to compensate for wear, or to increase or diminish the friction between the plates and the outer tube. hen the plates are l0ngitudinally raised with respect to the cone, the same will separate their upper ends and cause them to engage with the inner walls of the outer tube, whereby the two tubes are frictionally coupled together; but when the plates are lowered, whereby their upper ends are brought into range with a smaller part of the cone, they will move toward each other and release their grip upon the outer tube and permit the inner tube to be freely raised or lowered, as desired. As the two tubes are normally coupled when the standard is in use, the plates will necessarily be normally sustained in their lifted positions.

The particular means employed for moving the operating-rod longitudinally to shift the positions of the plates as desired and forsustaining them in their lifted positions may vary, and I do not confine myself to any particular construction or arrangementof devices for the purpose.

As herein shown, a hand-lever I, pivoted in a terminal J, secured to a threaded plug K,

located. in the upper end of the inner tube, is provided at its inner end with a cam L, which, when the outer end of the lever is depressed, engages with a fixed collar M, secured to the upper end of the rod H and moves the same downward against the tension of a spiral spring N, encircling the rod and interposed between the said fixed collar and the upper end of the cone B and operating to automatically lift the rod and recouple the two tubes after the outer end of the hand-lever has been relieved of pressure and to sustain the rodin its elevated position, and hence the plates in their operative positions.

If desired, the spring may be located at the lower end of the rod and the hand-lever may be replaced by a sliding collar encircling the upper end of the inner tube. I would therefore have it understood that I do not limit myself to the exact construction herein shown and described, but hold myself at liberty to make such changes and alterations as fairly gall within the spirit and scope of my inven- Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an extensible standard for pianolamps, the combination, with the outer tube thereof, of an inner tube terminating at its lower end in an inverted cone, a longitudinally-movable operating-rod located in the inner tube and projecting below the cone-shaped end thereof, two concavo convex frictionplates hung to the lower end of said rod and extending upward upon opposite sides of the said cone portion of the inner tube, a spring adapted to normally sustain said rod in its raised position and draw the said frictionplates upon the said cone and against the inside of the outer tube, and means, substantiallysuch as described, fordepressin g said rod and plates against the force of said spring, substantially as described.

2. In an extensible standard for pianolamps, the combination, with the outer tube thereof, of an inner tube located in the outer tube and terminating at its lower end in a cone, an operating-rod located in the inner tube and projecting below the lower end thereof, a collar adjustably mounted on said projecting end of the rod and provided at op- 

